About the replication strategy of Cassandra

[Kauzki Aranami]

Hi all. I am interested in the architecture of Cassandra.

Cassandra offers the replication policy such as "Rack Unaware" "Rack
Aware(within a datacenter)" "Datacenter Aware". It is necessary to
select these replication policies by the application.

The algorithm when the replication policy based on "Rack Aware(within
a datacenter)" and the "Datacenter Aware" strategy is selected might
be a little difficult. In Cassandra, Zookeeper was selected to the
election algorithm of the node that the system was using.


1.　Please give notes the replication strategy of Cassandra is selected.


2.　About the Zab protocol adopted with Zookeeper. The weak point of
the Paxos protocol of Chubby is a delay. Is the Zab protocol more
excellent than this Paxos protocol?


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  Kazuki Aranami

 Twitter: http://twitter.com/kimtea
 http://d.hatena.ne.jp/kazuki-aranami/
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